Wired for safety's sake

Check out the risks

Some wiring (e.g., knoband-tube, aluminum) can increase the chance of a fire. Some insurance companies want a guarantee that a home does not have this wiring, some may give you time to have it removed, while others might request an inspection to ensure its safety.

Photograph by: Thinkstock
, Postmedia News

Since electricity was first brought in to our homes in the early 1900s, various electrical wiring types have evolved, and all, if installed and maintained correctly, can be safe. However, if not installed or maintained correctly, each has potential risks.

My office receives inquiries from a growing number of people in older homes where insurance policies are being cancelled or individuals are unable to obtain new coverage because of electrical wiring. If you're one of the thousands of homeowners with knob-and-tube and aluminum wiring, understanding the way your house is wired can help you weigh your options about upgrading the electrical system for insurance coverage.

Some wiring (e.g., knoband-tube, aluminum) can increase the chance of a fire. Some insurance companies want a guarantee that a home does not have this wiring, some may give you time to have it removed, while others might request an inspection to ensure its safety.

Is it safe?

Many industry experts, including Hydro authorities and several licensed electricians, confirm that 60-amp service and both knob-andtube and aluminum wiring are not necessarily problems in themselves. They recommend inspection to ensure that the wiring is safe and adequate for the household.

Knob-and-tube wiring

Knob-and-tube wiring was in common use until the 1940s. More than 1.5 million homes across Canada were built with this early form of electrical wiring, which was used up to 1945. Many homes still have it, but it is considered too risky and dangerous to be insurable by some companies.

It comprises insulated wires clamped on two-piece porcelain knobs; positive and negative are carried separately. Hollow porcelain tubes carry the wires through beams and other combustible materials. Modern electrical codes do not permit this type of wiring. It can present a hazard if tampered with. The unsheathed insulation is subject to deterioration, particularly where it is exposed; that is, not enclosed in a wall or ceiling. Worn insulation, of course, presents a shock hazard.

The ESA's (Electrical Safety Authority) recommendation to insurance companies on knob-and-tube wiring is that they ask for inspections to make sure the wiring is safe. It does not recommend denying someone insurance simply because they have some knob-and-tube wiring, although individual insurance firms can refuse coverage for homes with this wiring as they see fit.

What you can do

The first thing to determine is the safety of your system. Even if your system is determined safe, consider upgrading at least parts of it. The areas of a knob-and-tube installation that are most vulnerable to mechanical damage and trouble are also those areas that are exposed and easiest to change.

About aluminum wiring

Houses with aluminum wiring are generally safe. Fuse panels can be upgraded to breaker panels quite easily, and at a lower cost than rewiring an entire home. The main areas of concern with aluminum wiring are your homes' connectors and receptacles. When adding to a circuit, always use connectors and adapters that are suitable for use with copper wiring. Consult an electrician if you have any doubts.

More to follow next week! For more home-improvement information, to send Shell an email or to find qualified electrician in your area, go to www.AskShell.com

Story Tools

Some wiring (e.g., knoband-tube, aluminum) can increase the chance of a fire. Some insurance companies want a guarantee that a home does not have this wiring, some may give you time to have it removed, while others might request an inspection to ensure its safety.

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